Nuclear and mitochondrial DNA sequences from two Denisovan individuals

Denisovans are a sister group of Neandertals that were identified on the basis of a nuclear genome sequence from a bone from Denisova Cave (Siberia). The only other Denisovan specimen described to date is a molar from the same site. We present here nuclear DNA sequences from this molar and a morphological description, as well as mitochondrial and nuclear DNA sequences from another molar from Denisova Cave, thus extending the number of Denisovan individuals known to three. The nuclear DNA sequence diversity among the Denisovans is higher than among Neandertals, but lower than among present-day humans. The mtDNA of one molar has accumulated fewer substitutions than the mtDNAs of the other two specimens, suggesting Denisovans were present in the region over several millennia.